* {
  margin: 0;
  padding: 0;
  text-decoration: none;
  list-style: none;
  font-family: sans-serif;
}
h1 {
  position: relative;
  margin: 20px auto;
  padding-top: 15px;
  width: 70vw;
  height: 12vh;
  text-align: center;
  background: rgb(143, 25, 158);
  color: white;
  font-weight: bold;
  border: 5px solid #ccc;
  border-radius: 20px;
}
h2 {
  text-align: center;
}
#calculadora {
  position: relative;
  margin: 20px auto;
  width: 390px;
  height: 600px;
  border: 1px solid #aaa;
  border-radius: 20px;
  background: #ddd;
}

#operaciones {
  position: relative;
  margin: 20px auto;
  width: 70%;
  background: white;
  border: 1px solid #ccc;
  border-radius: 10px;
  box-shadow: 5px 5px 10px #999;
  padding: 10%;
  text-align: right;
  font-size: 25px;
  overflow: hidden;
}

#calculadora ul {
  margin-left: 5px;
}

#calculadora ul li {
  float: left;
  padding: 32px;
  width: 10px;
  text-align: center;
  margin: 8px;
  background: white;
  border: 1px solid #aaa;
  border-radius: 5px;
  box-shadow: 5px 5px 10px #999;
  font-weight: bold;
  cursor: pointer;
}

#calculadora ul li:hover {
  background: cyan;
  color: white;
}

#calculadora ul li:active {
  background: magenta;
  color: white;
}

#borrar {
  position: absolute;
  bottom: 10px;
  padding: 5px 25px;
  width: 60px;
  background: magenta;
  border-radius: 10px;
  left: 150px;
  border: 5px solid #bbb;
  color: white;
  cursor: pointer;
}

#borrar:hover {
  background: purple;
}

#borrar:active {
  background: cyan;
}